3 sentences

1. 同性婚姻在一些国家是合法的。

   tóng​xìng hūn​yīn zài yī​xiē guó​jiā shì hé​fǎ de.

   Same-sex marriage is legal in some countries.

   Source: Dong Chinese Dictionary

2. 在这对同性情侣中，她是比较女性化的婆。

   zài zhè duì tóng​xìng qíng​lǚ zhōng, tā shì bǐ​jiào nǚ​xìng​huà de pó.

   In this same-sex couple, she is the more feminine 'Po' (femme).

   Source: Dong Chinese Dictionary

3. 磁铁同性相斥，异性相吸。

   cí​tiě tóng​xìng xiāng​chì, yì​xìng xiāng xī.

   Like poles of a magnet repel each other, while opposite poles attract.

   Source: Dong Chinese Dictionary